To appropriately fit an application with the ideal type of neoprene, durometer must be taken into account. Durometer is the measurement of a particular neoprene sheet rubber’s hardness or softness. The ability to manipulate synthetic compounds like neoprene allows for many variations of the same material. With so many variations like durometer and density, neoprene parts can be produced from the proper material that is appropriate for the application. Some of these applications will need a rubber that is easily compressible, and thus, a soft neoprene would be needed in order to get the job done. Or perhaps the application requires something that is able to stretch better than other materials, and so, an elastic neoprene would be ideal for the task. It may seem difficult to comprehend all these variations and what they mean, if it were not for the neoprene durometer rating.

Before trying to find the appropriate rubber type, it’s important to understand that, amongst others, there are two different forms of rubber: solid and cellular. Solid neoprene is dense and is more difficult to compress. Cellular rubber is the spongy form of neoprene and is easier to compress. Each type of neoprene is going to be better suited for a specific set of functions, and measuring durometer and density are some of the best ways to determine which applications the material would be best suited for. Within each classification of neoprene, durometer is measured on the appropriate Shore scale. Here is a simplified breakdown of the Shore scales:

• Shore A Scale: Solid neoprene is measured on the Shore A scale, the most common scale for elastomers (http://www.bluerealmstudios.com/2009/02/25/understanding-shore-hardness/). Other items measured on the Shore A scale include rubber bands (30 Shore A) and tire treads (60 Shore A). Since solid neoprene can be manufactured with varying durometers, choosing the right type of neoprene is dependent on the application. Durometer correlates with a material’s density. Neoprene with a lower durometer like soft neoprene (45 Shore A) would take less pressure to compress than a higher durometer product like hard neoprene (65-75 Shore A).
• Shore 00 Scale: The Shore 00 scale is used to measure cellular neoprene and other soft, easily compressible elastomers. Gummy bears (10 Shore 00) and gel shoe insoles (30 Shore 00) can also be found alongside cellular neoprene in this scale. Just like its solid counterpart, cellular neoprene is available in a range of durometers that can suit a number of specialized applications. It is important to know which scale to use for each type of neoprene so that mistakes are not made when it comes to actually using the material!

Of course, there are some slight exceptions. A common use for both solid and cellular neoprene is as a gasket or weather stripping. As a general rule, a material with high compressibility like soft neoprene ensures a tighter seal. Yet, at the same time, a gasket should be resilient enough to withstand the physical abuse from more demanding applications. The material should not be so compressible that the two connecting parts come into contact. In this case, it is best to use a neoprene which is balanced in its qualities, but could feasibly come from either of the two scales. More keen research is needed to effectively determine which kind of neoprene sheet rubber will work best.

For less critical applications of neoprene, durometer and density specifications come down to the preference of the user. For example, solid neoprene sheet rubber fabricated as a bumper or pad does not need a precise durometer in order to be effective; soft neoprene is used as a material for a laptop protector and any task that needs a material specifically for its ability to expand will want an elastic neoprene. Once again, it comes down to preference. Consider your application and try to determine how crucial it is to know both durometer and density; neoprene in its many forms is beneficial for a wide array of uses.